I try to do daily, or nearly daily programming exercises and demos to improve my skills. The more complex demos go into the Swift-Sandbox repository. The simpler exercises go here. I try to keep the exercises to a single file, with comments, explanation and sample output. Most of these are XCode playgrounds.
DesignPattern-Memento
DesignPattern-Iterator
DesignPattern-Composite
DesignPattern-Mediator
DesignPattern-Visitor
DesignPattern-Visitor
DesignPattern-Strategy
DesignPattern-TemplateMethod
DesignPattern-Proxy
DesignPattern-Flyweight
DesignPattern-ObjectPool
DesignPattern-Decorator
DesignPattern-Builder
DesignPattern-Facade
DesignPattern-Bridge
DesignPattern-Adapter
DesignPattern-AbstractFactory
DesignPattern-FactoryMethod
DesignPattern-SimpleFactory
DesignPattern-Prototype
DesignPattern-Singleton
Enums
ProtocolOrientedProgramming-ShapeRenderer
Algorithms-Sorting
RetainCycles
FizzBuzz
BinarySearchTree
Exceptions
MapFilterReduceFlatmap